DESCRIPTION Veterans with Parkinson's disease (PD) have impaired mobility, which adversely affects their quality of life. The candidate has demonstrated the effectiveness of adapted tango dance, in which participants both lead (internally guide: IG) and follow (externally guide: EG) movement (Hackney & Earhart 2009, 2010). To improve outcomes, the underlying neural mechanisms for both motor impairments and improvement must be investigated. IG and EG movements have distinct neural patterns. Individuals with PD have trouble with IG movement but this problem is helped by strategies employed while leading. During following, participants with PD can exploit multiple external cues, which facilitate movement in PD, because EG tasks bypass the basal ganglia (Freedland et al., 2002). In older veterans with PD, we aim to determine neural activation patterns during IG and EG lower limb movement and then examine effects of IG and EG training on neural activation in conjunction with mobility improvements. The long-term goal is to optimize motor training for veterans with PD by understanding lower limb motor circuitry in PD as well as neural changes in circuitry through which training is effective. The objectives are as follows: 1. To explore neural activity of lower limb movements in veterans with PD under IG and EG conditions, and then to evaluate neural changes in circuitry after IG and EG training through adapted tango, using a randomized controlled trial design 2. To gain expertise in imaging of complex neuromotor systems of veterans with and without PD, and then apply this expertise to the evaluation of neural circuitry changes as a result of training. 3. To gain further experience in rehabilitative study methodology. 4. To Improve hypothesis generation, reasoning ability and problem solving while investigating PD motor impairment, its underlying mechanisms and response to targeted training. Mentoring: The mentoring team combines faculty with expertise in fMRI, rehabilitative clinical trials, and the care of persons with PD. Mentors include Krish Sathian, MD, Ph.D. (Primary, neurology, imaging), Steven L. Wolf, PhD. PT (motor rehabilitation, clinical trials), Daniel Corcos (PD, imaging, motor rehabilitation) and Bruce Crosson (PD, imaging, neurocognitive evaluation), Ph.D. Marian Evatt, MD and Kaundinya Gopinath, Ph.D. will serve as clinical and research collaborators, respectively. Career and Research Plan: Career development activities include coursework and seminars in neuroscience, imaging, statistical and rehabilitative methodology. The candidate's mentors will provide structured readings and discussions on motor systems, the pathophysiology of PD, motor rehabilitation and imaging applications. The research plan will begin with an fMRI investigation. We will examine neural correlates of a clinically-used foot-tapping task, during IG and EG conditions in veterans aged 40-70 with and without PD. Then, we will assess the relative effectiveness of IG versus EG training during an adapted tango class, compared to a behavioral control for improved mobility and foot tapping, Participants with PD will be assessed for disease severity, and will receive tests of outcome measures while OFF medications, 1 week before training, and 1 week and 1 month after training. Participants must attend 20 lessons of IG or EG adapted tango in 12 weeks, taught by an experienced instructor. In an fMRI scanner, we will assess participants for improved foot tapping after training and investigate changes in activation in specific neural circuits in conjunction with training effects upon mobilit. The candidate expects the proposed career and research plan will prepare her to apply for Merit Review funding to establish independence as an investigator. This plan will also provide greatly needed evidence to support guidelines for the treatment of motor impairment in veterans with PD.